Conventional X-ray devices typically have an X-ray source and an X-ray detector. For an X-ray image recording, a sampled object is positioned between the X-ray source and the X-ray detector. In an X-ray device for medical uses, the sampled object is usually a patient. X-rays are then projected by the X-ray source onto the sampled object. The X-rays penetrate the sampled object and, in the process, are differently attenuated (depending on the density of the sampled object). The intensities of the X-rays (transmitted through the object and therefore attenuated) are detected by means of the X-ray detector.
A distinction is made between indirect-conversion X-ray detectors and direct-conversion X-ray detectors. In order to detect the transmitted X-rays, an indirect-conversion X-ray detector has a sensor layer in the form of a scintillator layer which is sensitive to X-ray radiation and which converts the incident X-ray radiation into visible light. The visible light is then converted, by means of a photodiode, into an electrical signal. In the case of a direct-conversion X-ray detector, the sensor layer is made of a semiconductor material (e.g. cadmium telluride) in which incident X-ray radiation is directly converted into an electrical signal.
Against the background of simple and economical manufacturing of a large-area X-ray detector, the entire detector surface is often composed of small, individually produced units which are referred to below as detector elements. Each detector element herein usually comprises a plurality of detector pixels. This means that each detector element can detect a plurality of signals in a spatially-selective manner and in parallel which, in a subsequently-formed matrix image composed of all the signals (of all the detector elements), each represent an image point of this matrix image. The detector elements themselves are typically arranged in rows or in an array.
Further electronic components which are directly associated with the sensor layer and are configured for reading out the signal from the sensor layer—for example, photodiodes, capacitors, optional analogue-digital converters or the like—are also arranged on the detector elements. The signal, or each signal, detected by the detector elements is usually read out by way of a downstream electronic control unit, further processed (particularly digitally) and prepared for passing on to a downstream image processing unit.
The detector elements are typically operated with a relatively low voltage (often smaller than 5V). This voltage is usually generated by a (central) voltage supply unit for all the detector elements together and distributed to the detector elements. However, due to the often relatively large extent of the detector area and the long electrical transmission routes resulting therefrom, relatively large power losses typically occur along the electrical conductors. In the event that the X-ray device is a computed tomography device (in a tubular construction, also known as a gantry construction), the individual detector elements are arranged, for example, over a length of, for example, 1 m.